In the past several years, privacy risks of computers' users encountered through Internet use have risen dramatically. The privacy risks can range from the gathering of statistics on users, to malicious acts such as the spreading of spyware and various forms of bug exploitation.
The most common concern in the field of privacy relates to cookies, log files, history files or other personally identifiable information placed on a user's computer during web sessions. Cross-site scripting or other techniques may be used to steal this information from a user's computer. For example, information about person's financial transactions may be compromised. Some browsers offer the option to clear cookies and history automatically whenever the user closes the browser. However, some private information such as log files cannot be deleted. Moreover, private information from the computer may be stolen during an Internet session before cookies and history are cleared.
Another concern relates to web sites visited during a web session. These web sites can collect, store, and possibly share personally identifiable information about users. In addition, users obtain Internet access through an Internet Service Providers (ISPs). All Internet data to and from the user must pass through the ISP. Even if users encrypt the data, the ISP still knows the IP addresses of the sender and of the recipient. Therefore, any ISP has the capability to observe everything about the user's Internet activities. The advent of various search engines and the use of data mining created a capability for data about individuals to be collected and combined from a wide variety of sources very easily.
An anonymizer or an anonymous proxy is a tool that attempts to make activity on the Internet untraceable. It accesses the Internet on the user's behalf, protecting personal information by hiding the source computer's identifying information. However, the anonymizer itself may cause a privacy concern. The anonymizer can read and modify content of the information that the user is sending or receiving. It can intercept and record private information, such as username and password credentials, credit card numbers, that have been transported using the anonymizer. Moreover, even trustworthy anonymizers cannot provide protection for e-mail or chat services. Also, they cannot filter out any malicious code that may reveal the identity of the user who wishes to remain anonymous.
Therefore, there is a need for a comprehensive privacy protection system that would address multiple aspects of data privacy protection while providing sufficient flexibility to enable a computer's user to access required network resources.